Whether or not you are likely to have thinning hair -- or go completely bald -- is pretty much outside your control. Sorry, folks, but when it comes to hair loss, the process is almost 100 percent genetic. (So if you find you're losing hair, you might want to have a word to your parents.)

However, that's not to say you are powerless to stop the process, with treatments available to combat balding (as well as to stimulate hair growth) which have proved largely effective.

But what is the deal with hair loss in the first place? Why does it happen, how can we stop it and does it differ between men and women?

"Think of the the upper lip of a teenage boy. A boy starts off with tiny little hairs which are almost invisible -- those tiny, wispy little hairs -- which eventually grow stronger and larger until that boy has a full beard or mustache.

"Interestingly, the same process is happening in the exact reverse on scalp."

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A helpful diagram of a man in the varying stages of baldness.

While hair thinning/hair loss may affect women differently to men (more on that later), the cause behind it is essentially the same.

Basically, FPHL occurs when a woman who is already predisposed to the condition (thanks, Mum and Dad) is exposed to androgens. (Just because androgens are male hormones, it doesn't mean women don't have them).

Much like in men, those pesky, hair-hating androgens then minimise susceptible scalp follicles until they become so small they are no longer able to support normal hair production.

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Interestingly, even bald men should have no issue with growing a beard.

How do I know if it's happening to me?

Well, we don't know how to put this delicately... but you will wake up one morning and all your hair will be gone.

KIDDING.

Hair loss is an ongoing process that presents differently in men and women.

For men, they are most likely to first notice a thinning of hair at the back of their scalp and above the temples.

As for FPHL:

"Female pattern hair loss begins with diffuse thinning over the top and front parts of the scalp, most noticeably in the centre," Sinclair wrote in an article published to his website. "While the hair loss is most pronounced on the crown, hair can also thin from ear to ear. The back of the head is least affected."

Many women with FPHL will notice they are shedding an increasing amount of hair or that their hair has reduced in volume or has less body. Women who have long hair may notice their ponytail becoming thinner.

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While shedding hair is completely normal, many women with FPHL will notice they are losing an increasing amount.

What can I do?

Luckily, there are a host of successful treatments out there on the market which can assist in preventing hair loss as well as stimulating hair growth.

It's extremely important to note that time is of the essence when it comes to treatment: the sooner you start, the better results you'll get.

For women, the process is somewhat simpler as they can simply take oral anti-androgen medication, which basically block the effect of androgen hormones. (Note these should not be taken if the woman is pregnant).

According to Sinclair, there are also a number of a number of shampoos and conditioners on the market which can reduce hair loss and promote regrowth.

While women are likely to experience success with oral anti-androgens (90 percent, in fact) the process is not as straight forward for men due to the fact anti-androgen treatments are not just specific to the hair follicle. (In Sinclair's words: "if you give men anti-androgens, you'll emasculate them and that's horrible.")

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In men, hair loss is often first noticeable around the temples.

Or in other, non-scientific jargon-y terms, it stops testosterone from being converted into a more active by-product dihydrotestosterone (DHT) which has a more profound effect on the androgen receptors.

By using finasteride, Sinclair says "you can block the conversion of testosterone to DHT, which is enough to stop the badness without emasculating men."

While Sinclair notes stopping the DHT production is enough to stop balding process in 98 percent men, around one in 200 taking finasteride may notice a reduction in their libido.

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The other place men might initially notice hair loss is at the back of their head.

"Minoxidil is moderately effective.It's nowhere as near as effective as the tablet but for some people, it will stop the hair loss and stimulate hair to regrow," Sinclair told HuffPost Australia.

"There are also some complaints because it is put in a base that makes the hair look oily and sticky. For those attempting to grow more hair, it can make their hair look worse," Sinclair continued.

"I have seen people take it for years and years with success, but many more than that found it too time consuming or didn't like the look or feel. In short, they would rather go bald than continue using it."

In terms of how the treatments compare, Sinclair sums it up best on his website.

While finasteride works best at arresting progression of genetically programmed hair loss, some men will achieve partial regrowth. The sooner you begin treatment, the more hair there is to protect.

Minoxidil is better at stimulating new growth rather than preventing progression. A bit like the bank manager who lends an umbrella when the sun is shining, and wants it back when it starts to rain, minoxidil works better before you go bald. Men who still have hair regrow more hair than men who have lost it all.

When used together, the combination of minoxidil and finasteride is a man's best chance to both arrest hair loss progression and maximise hair regrowth.